The Zodiac is the name of the virtual belt in which the
planets,
Sun, and
Moon
appear to move about the sky. In reality, the
planets and their respective moons
(most of them anyway) orbit the
Sun about the same plane. Because the orbits of
the
planets are not on a perfect plane, the Zodiac band is 16°
wide - 8° on either side of the
ecliptic.

When mentioning the
Zodiac, the subject of Astrology also comes to mind. Astronomy and Astrology are
not the same thing. Astronomy is a science while Astrology is not. The
pseudo-science of Astrology plot the positions of the
Sun and planets about 12
constellations that constitute the Zodiac. The result of these positions is the
effect the given planet,
Sun or
Moon on your birth sign. There are two problems regarding this
plot: there are 13 constellations in the Zodiac and the position of the
Sun within the Zodiac was plotted 2000 years ago. Because the
Earth in inclined by
23.45 degrees, it rotates like a top. This is called precession.

Precession is the act of a planet spinning
like a top. Click on the image to view a demonstration of precession.

Because our planet Earth is tilted by 23.45 degrees, it also precesses.
The result will be a shift in the position of the constellations
relative to us on Earth (video care of
Swinburne
Astronomy Online).

The result is
shifting of the constellations. This means that the Astrological plots and
predictions based on your birth sign are really off by one month. For example, I
was born in early March so my Astrological birth sign is Pisces. In reality
however my birth sign is Aquarius since the
Sun was in this constellation when I
was born.

Of course, I do not believe in the predictions of Astrology simply
because the other eight planets have no affect on life here on
Earth. If this
were so, then the orbital speed of the
Earth will gradually decrease since the
more massive
planets orbit the
Sun slower than the
Earth. This is simply not the
case. However, it should be noted that the
Sun and
Moon do in fact influence
Earth in a number of ways to include
weather and
tidal changes. As far as
personality, wealth, health and relationships, there is no scientific evidence
to prove these effects.

For a comparison
to the current dates of the Zodiac versus the Astrology plots, click
here to view the table at the bottom of this page.

The following table introduces the 13 constellations that make up the Zodiac -
the large bright object in each of the images is our
Sun:

In Greek mythology, Aquarius (also known as Ganymede in Roman myth)
was a beautiful young boy whom Zeus brought to Olympus to be the cup
bearer of the Gods. It is suggested that Zeus fell in love with
Aquarius.

In Greek mythology, the ram
carried Athamas's son Phrixux and daughter Helle to Colchis to escape
Ino. When the ram reached Colchis, Phrixux sacrificed the ram and hung
its fleece in the Grove or Ares. This fleece turned to gold and later
was the quest of Jason and the Argonauts.

The constellation name was common in Greek, Babylonian and Egyptian
cultures.